Automatic railway couplers



July 16, 1963 P. E. E. A. A. HENRICOT 3,097,751

AUTOMATIC RAILWAY COUPLERS Filed July 24, 1959 4 Sheets-Sheet 1 FIG! 1 I ZII I/ """0/////////A mvsmon. Poul Emiie Ernest Alfred Andre Henricot MJ/W y 1963 P. E. E. A. A. HENRICOT 3,0 ,75

AUTOMATIC RAILWAY COUPLBRS Filed July 24, 1959 FIG 4 9 FIG 5 4 Sheets-Sheet 2 INVENTOR.

Poul Emile Ernest Alfred Andr Henricot BY M WKM

Afl'ys y 1963 P. E. E. A. A. HENRXCOT 3, 5

AUTOMATIC RAILWAY COUPLERS Filed July 24, 1959 4 Sheets-Sheet 5 F167 FIGS 1 INVENTOR. Poul Emile Ernest Alfred Andre Henricot BYMkZZZM Attys y 1963 P. E. E. A. A. HENRICOT 3,09

AUTOMATIC RAILWAY COUPLERS Filed July 24, 1959 4 Sheets-Sheet 4 IIIIIIIIIIIIIIIIIIII/ 51 52 5a (55 57 I 7\ Q/ ss 55 5s 54 INVENT OR.

3,097,751 Patented July 16, 1963 ice 3,097,751 AUTOMATIC RAILWAY COUPLERS Paul Emile Ernest Alfred Andr Henricot, Curt-St.-Etienne, Belgium Filed July 24, 1959, Ser. No. 829,266 9 Claims. (Cl. 213-152) The present invention relates to automatic center buffer couplers of the movable knuckle type and more particularly pertains to improve their structure in order to adapt them to present-day or near-future requirements recapacity and safety of operation, whilst taking due regard to the necessity of overcoming transition difiiculties in net works passing over from an older type of different coupler to automatic central buffer practice in the course of their development.

It is a matter of record that in the most progressive railways in the world, the heaviest type of automatic coupler now existing is scarcely able to cope with the heaviest trains whilst working over difiicult mountain grades; couplers are working dangerous near their limiting breaking strength, failures due to overload become common, and yet the demand is increasing for higher capacity and speed of goods circulation. Also in view of this demand, only an essentially unavoidable increase in deadweight of the coupler could be allowed.

So a primary object of present invention resides in increasing the strength of the coupling gear, without making it unduly heavy.

Another object is to assure straight line transmission of traction and buffing forces, as directly as possible.

A further object is to ensure most adequate distribution of material or metal between the elements of the castings assembly which constitute the coupler, so that each part sustains its fair share of the load, strain equalization being pushed as far as consistent with normalized dis tribution of stresses and the necessities of operation.

Another particular of the invention is to localize an important part of stress transmission within the knuckle, considered as a curved link, so that this important element, which is also the component part destined to concentrate service wear, will act as a safety feature for protecting the assembly.

Finally, it is also intended, in view of the heavier and speedier trafiic producing a higher level of shock and vibration, to provide multiple overlapping safety features for an increased security of operation, and to build a strong coupler aslight as possible.

Means to this end essentially consist in localizing an important part of stress transmission within the knuckle, considered as a curved link under traction or buff, and in correspondingly modifying co-operating parts of coupler to best answer service requirements.

The knuckle has also been designed to concentrate the inevitable wear occuring in service, but its active outside contour (the well-known 11' A profile of Association of American Railroads) has been developed as an assembly of smoothly-blended curves in order to minimize frictional abrasion. It is also formally intended that, in case of brutal overstress the knuckle should fail before permanent injury accrue to more expensive elements: yet its resistance is the limiting factor for the ultimate strengthwhich it is desired to increase-of the automatic coupler assembly.

On the other hand, quickness and ease of replacement in case of damage or excessive shape reduction or distorsion is desirable, and this constitutes a supplementary object of the invention.

Particulars of the above will be apparent from the description given of annexed FIGURES 1 to 11, in all of which each reference number given is used to nominate one same constituent element throughout. For the sake of clarity, not essential elements have been omitted from drawings.

FIGURE 1 shows in side elevation the essential part of automatic coupler according to the invention, partly in section, the so-called guard arm, i.e. the portion in front of line I-I on plan view FIGURE 6 having been removed.

FIGURES 2 and 3 show inner views of the two halves of coupler casting as they would appear when, after removal of inner parts, it were sectioned along line IIII of FIGURE 1, top portion turned over and both halves considered from above. FIGURE 3 more specifically gives an alternate embodiment of the invention, and in both figures, dot lines giving the outer contour of knuckle lines have been added for purpose hereafter explained.

FIGURE 4 gives a top view of knuckle.

FIGURE 5 shows a vertical section through assembled coupler, substantially along line V-V of FIGURE 6.

FIGURE 6 is a sectional plan view, similar to FIG- URE 2 but with essential inner elements maintained, explaining sundry preferred embodiments of invention.

FIGURE 7 is .a sideway view of lock of coupler according to the invention, in assembly with its lock-lifter and positioned within the surrounding elements of the coupler, in order to show its performance.

FIGURE 8 is a separate view of lock-lifter, assembled with its operating lever and lock.

FIGURE 9 shows side elevation of coupler according to the invention, with transition arrangement moored in unopcrative position.

FIGURE 10 is a XX of FIGURE extended.

FIGURE 11 gives separate side elevation of transition arrangement.

The automatic coupler 1 is essentially composed of box-like casting 2 containing the mechanism and rear- Wardly terminating in the shank or drawbar 3 (whence it is also comprehensively called drawbar in USA terminology) by means of which it is connected to the vehicle frame through a draft gear adapted to cushion shocks in traction and in buff.

Front end 4 of this box-like casting 2 has to be rather widely open at 8 in order to allow swinging movement of the knuckle 5, the nose -12 of which when open forms, together with the guard arms 6 of coupler casting, an opening apt to meet and coaxialize with a like opening of an approaching similarly disposed assembly, both progressively closing on and by one another, until the locks 11 of both couplers fix knuckles latchlike in closed position in which the opposed inner surfaces of the pair of noses 12 are disposed in engaging relation to prevent separation of the knuckles from each other.

The vertical central portion 4 of the front face of the coupler casting box, after gently pushing the opposite knuckle into closed position, as soon as this latter can recede no further, has to take up the remaining impact force of the mating vehicle, and consequently acts as a. buffer to the opposing knuckle.

In order that bull-mg forces may be well centered, the guard arm 6, preferably comprises a powerful solid horn, protruding to the right of the normal buffin g face 4 when facing the coupler. The guard arm is dimensioned adequately to resist some shock abuse, and cooperates with the knuckle 5 which is rotatably hinged on the vertical pin 7 between two (an upper 9 and a bottom 10) salient wings at the left of the boiling face of the mating assembly.

It is well known, in order to relieve the knuckle pivot pin 7 of the stresses caused by buff and traction forces, to provide both top and bottom of the knuckle and inside faces of the knuckle-carrying wings 9, 10 of the coupler plan view of same, sectioned along 9, showing part of transition gear casting 2 with mutually corresponding lugs substantially concentric to the fulcrum, and closely engaging one another when coupling is being effected, whilst some notable freedom is intentionally foreseen between the pivot pin and its bores in the knuckle and the wings. In this fashion, transmission of forces is almost totally effected between the knuckle and both the wings, and moreover the lugs situated in the wings or in their immediate neighbourhood are rather easily accessible for fitting or adjustment if required.

This possibility of adjustment, helpful in old days as allowing correction of casting imperfections or faults, constitutes a point of danger when coupler elements are subjected to high stress requirements. Fitting, however skillfully carried out in the cramped surroundings offered by the inside of coupler casting 2, could at best be a removal of obtrusive salients and was unable to create the snug application of corresponding surfaces intended to transmit stress. Contacts took place on ridges and points, soon flattened out under load with resulting excessive play between parts. Real relief of strains on pivot 7 by lugs 16 and 17 on knuckle could only be obtained when the art of casting had progressed sufhciently to insure precise mating of correspindong surfaces with one another within tolerance limits which for rough castings are narrow and only obtainable through diligent use of perfect molding practice and accurate gauge-checking of parts.

Bufling forces, as said above, mainly taken up on the centre face of coupler casting, only partly afiect lateral wings, and moreover, due to the adoption of continuous braking, buffing forces tend to become in normal cases more progressive than they used to be. On the contrary, tractive stresses increase with train loads; therefore, the deposition of such protection lugs on the coupler casting wings is apt to overstress said wings locally, also to cause lateral expansion as the knuckle inserts its own lugcarrying hub wedge-like between wings, because said wings cannot be braced against one another by intermediate tractional struts. In the following, tractive stresses will be mainly considered.

In the known art, the knuckle, receiving the direct stress of traction or buff, acted as a double-arm-lever, just reversing direction of forces and imposing on coupler casting 2 a reaction of substantially equivalent strength, in the direction from lock 11 to lateral Wings 9 and 10. It appears to be a worthwhile improvement, when, according to the invention, a traction exerted on nose 12 of knuckle is transmitted by said knuckle, acting as a curved link, to points situated symmetrically and as near as possible to the draft gear, which is to be the final recipient of the load, without substantially influencing wings 9 and 10. It has been proved by strain gauge measurements under static load that final stresses in the vicinity of the wings are reduced over 50 percent.

According to the invention, this serious improvement is brought by disposing broadly extended lugs 22, 23 on top and bottom portions of the knuckle tail, which must for other reasons have a notable arcuate extension. These lugs can thus have a considerable area of contact with their respective counterparts 24, 26 and 25, 27 inside coupler head casting without needing too notable a height, due to their extension over a long are. Opening 8 in coupler front wall 4 (buffing area) does not require to be excessively widened. Lugs, solidly braced, offer a sturdy resistance to flexure. Their implantation in the proximity of the root of coupler shank has the advantage of almost direct transmission of effort to said shank by means of a box-like, continuous structure, instead of (as was the case previously), immediately through an intricate system of walls, which in the neighbourhood of points of application (wings) is rather weakened by the big opening for the knuckle.

Maintaining, together with the new arrangement (22, 23, with their correlatives 24, 25, 26, 27) also the previously used protections such as 16 and 17 situated on knuckle nearer the location of pivot as well as their counterparts within the coupler casting, has been found especially valuable if tolerances can be so arranged that pairs of corresponding ledges and lugs make contact successively as they are reached when proceeding from the tail of the knuckle towards the pivot. It will be understood that increasing loads acting on nose 12 of knuckle will stress said knuckle, especially its weakest hind parts; these will have tendency to stretch, so that ledge 17 will come to bear against its counterpart in the coupler casting 2, which will take up a part of the load; and finally protection 16 will also engage its corresponding seat in the wings, giving the latter an opportunity to come to the rescue.

Knuckle 5 may also according to the invention, catch with its extreme tail end 28 behind a lug 29 inside of box part of coupler casting, thus extending on a third side the hook-like arrangement linking it to the former for direct transmission of forces. Even the lock-touching side of knuckle can be shaped as at 30 in order to coact with ledge 31 on lock 11, giving a four-side mutual engagement. This latter disposition, of course, will only be effective as far as:

(a) The lock, vertically bridging gap 8 in front striking face 4 of coupler, is apt to resist the fiexural strain now exerted upon it.

(b) Said bearing stresses can be taken up by solid walls on top and bottom sides 32, 33 of gap 8.

In the known art, lock 11 was essentially intended as a compression-stressed member, for assuring knuckle unmovably in locked position by filling the space between face 34 on guard arm and substantially parallel face 35 on knuckle: when lock 11 is completely lifted, edge 36 on knuckle is free to swing out through gap 8 in front face of coupler casting 2, thus releasing the mutual grasp of the knuckles: gap 8 extends into guard arm 6 just enough to make this possible. Thence, in known couplers, lock 11 exerts on knuckle a compression reaction transverse to the direction of pull, and to maintain equilibrium of system a complementary reaction is needed acting in direction to pivot 7. The result was a severe stressing of coupler head wings, the knuckle thus acting only as a stress-reversing lever linkage.

Quite a different picture obtains with the arrangement according to the invention. Thanks to arcuate lugs 22, 23 and their derivatives coacting with their counterparts Within the coupler head casting 2, traction is directly transferred to the root of the shank 3, and as stated above, the coupler casting is seriously relieved of strain, whilst the knuckle is not notably overstressed.

In FIGURE 2, where the contour of knuckle nose has been shown in dotted lines, tractive load on knuckle may be roughly imagined to be transmitted to the centre of ledge 26, along line 37, forming an angle a with axis line of coupler.

In FIGURE 3, also representing one of the inner views of coupler casting 2, an alternative shape of lug 24 has been represented, markedly shortened in its extension towards guard arm face 34. Here the transmission of pull may be considered to happen along line 38, making with axis line an angle a, which is greater than or in FIGURE 2.

Of course, FIGURES 2 and 3 with or different from a should not be construed as referring to the same coupler: it is an essential requirement of good design that as far as possible all correlative part be equally, i.e. symmetrically stressed, and therefore a construction as symmetrical as possible is a first necessity. In cases where, due to stringent operational conditions, symmetry in shapes cannot be observed it is imperative to seek adequate compensation in sections.

Now reverting to angles or and a, as characteristic of two coupler constructions, we perceive that from one side a small or gives an almost straight-line axial transmission, but from the other a big it brings chord 38 much nearer 'lock, in closed position, lodges to the neutral fibre of the curved link, thus reducing flexural strains on the knuckle. Grossly, increasing a will relieve the knuckle and load the coupler casting more severely. Having, in accordance with FIGURE 2, almost halved strains on coupler head, the above consideration will provide those skilled in the ant with a welcome choice for compensation. Conversely, with increasing a, the lock and also the wings of coupler casting will be more heavily loaded.

Known locks have occasionally shown traces of beginning collapse under extreme stresses. Therefore, accordsing to FIGURE 7, the lock 11 is a solid block of adequate section and made of steel of sufficient hardness. Since the lock has to present an internal slot 40 for accommodating the trigger or lock lifter 41, the invention is carried into effect by disposing said slot sideways of the location of buckling stresses, reducing its size to the utmost. Lock lifter 41 after FIGURE 8 is made as thin as consistent with its accessory but important functions of safety fior preventing the lock from jumping loose under the elTect of traffic vibrations. For this same object, the

its ledge 42 beneath a protruding ridge 43 on rear face of coupler casting, so as to offer a supplementary security any unlocking tendency not caused by wilful actuation of uncoupling gear.

Safety of locked position is assured by the longitudinally slotted head 44 of trigger 41 engaging by gravity beneath ledge 45 in coupler casting 2: thus any ascension of the lock-tnigger assembly in the relative positions as represented in FIGURE 7, is precluded even if the lock, normally pressed between guard arm and knuckle faces 34 and 35, under vibrations of traific with momentary release of pressure and upward jerks, had tendency to creep upwards. This will be prevented by the barrier constituted by trigger head 44 catching against ledge 45, unless trigger 41 be positively lifted in a continuous movement so that by virtue of oblique slot in head 44, trigger head disappear within lock 11, which lifted eccentrically, will rotate around its resting points 46, so that ledge 42 will avoid fouling ridge 43. According to the invention, ridge 43 and ledge 42 would co-operate for safety in the case trigger 41 should fail to drop into full-down position on closing of knuckle, which is very improbable indeed since trigger 41 has ample play within its slot and around its axle 47, and is moreover weighted by the lever 48 actuating it, by means of eyelet 49.

The knuckle, now working as a nearly independent curved link for assuring transmission of traction in an approximately straight line, can be dimensioned in closer approximation to the theoretical problem of stability without however losing sight of several conflicting facts: sundry essential sections of the curved link are limited by the measurements of standard AAR coupling contour which have to be followed to enable coupling; they are moreover forcibly weakened by the pivot pin bore; although the knuckle structure ought to have a break strength of the order of size of the coupler head, it is apposite, both from economy, safety and quickness of renewals viewpoints, that this element, designed to concentrate wear and consequently intended as a light, quiclc ly interchangeable spare part, should also in case of excessive stresses, be the first to fail, before more expensive elements sustain permanent strain injury.

It is clear, considering the curved beam in flexion, that the deletion-stressed fibre of same should be as smooth and continuous as possible, carefully avoiding any configuration likely to produce a notch effect: rounded edges and gradual transitions are imperative, as far as they do not unfavourably effect the design of correlative elements in the coupler head.

0n the other hand, the presence of the pivot pin bore entails a considerable weakening of an important section of the knuckle hub under flexion. This pin, since the knuckle must be introducible into the coupler casting in just one definite position for assembly and disassembly if 6 required, strictly serves only to maintain the coupler elements together in this open position.

Section MN through knuckle hub is most severely stressed, the N side being under traction, the M side under compression: on static breaking tests, rupture initiates on N side. Pivot hole, in known art, centrally situated in the hub, is required to accommodate a 1%" standard pin. A pin of diameter appears satisfactory for the purpose intended, and with hole location within the usual disposition in outside tangential position, will procure on extra thickness of metal on the tractive side of hub, without reducing the compressed area, which can safely sustain about 30% extra unit load; so that an improved balance of strains is obtained. In other Words, referring for example to the knuckle hub section M-N as shown in FIGURE 4, the pivot pin hole may be reduced from a standard 1% inch diameter to a inch diameter, and the axis of the hole shifted laterally outwardly (upwardly in FIGURE 4) toward the compression side of the knuckle hub. In this manner, an additional inch is added to the tension side of the knuckle hub cross section MN, and the compression side of the cross section remains the same. It will thus be understood that in accordance with one aspect of the invention the pivot pin hole is located eccentrically with respect to the knuckle .hub, in the sense that the tension side or N side of the hub cross section is of a greater lateral dimension than the compression or M side of the cross-section.

The pivot pin holes in the knuckle-carrying wings 9 and 10 may also be shifted laterally outwardly in a fashion similar to that described above regarding the hole in the knuckle itself, as indicated by the location of the pivot pin hole in FIGURE 10. This off-centre disposition of pivot 7, as represented on FIGURE 10, also procures an improvement in coaxialising capacity of coupler, since the knuckle can now swing out to an extreme position more remote from coupling axis before incurring the danger that the push reaction any part of the opposite coupler may exert on it should fall outside the pivotal area and as a consequence fail to produce the in wardly directed moment required for closure and correct locking of knuckles. Due to this feature, coupling capacity, i.e. the distance which may exist between the axis of two couplers engaging with one another from knuckle side, may be increased by twice the displacement of pivot centre away from coupler axis line, an advantage not to be disregarded.

In a general way, optimum stress repartition would require the rear lugs, and also the knuckle-carrying wings, to be positioned symmetrically above and below the horizontal central plane of shank, which should also preferably contain the centre of locking area 35 of knuckle. This, however, is not always possible: space left available beneath intercommunication gangways of vehicles may impose drastic reductions in height of coupler above central traction plane, also mechanical necessities of the inner mechanism of couplers may impose limitations in either sense. However, each time the equilibrium of loads is disturbed, equalization of stress should be sought by an apposite increase in section of the member sustaining the higher load.

Conditions of this order typically arise when, for purposes of conversion (i.e. changing over from old type like hook and screw coupling to the automatic central buffer) an extensible shackle and screw coupling gear in accordance with FIGURE 11 has to be incorporated into a normal automatic coupler.

The transition gear according to the invention comprises a shackle 51 suitable to be slung over the normal hook of opposing vehicle, carrying an internally thseaded nut 52 outwardly journalled between flanges of said shackle by two trunnions, said nut engaging a hollow tube 53 outwardly threaded over its entire length and terminating by a handle 54 allowing to rotate it. Inside,

near the handle end, said tube 53 carries an internal thread of reverse sense to the outer one, which engages in nut fashion with a similarly threaded solid screw 55, terminating in a cross-wise placed double trunnion 56 at its end farthest from shackle. Said double trunnion registers with the inside cavity inside a transition-gear carrier, a steel casting 57 allowing angular movement in the plane of FIGURE 11. The gear carrier 57 itself terminates likewise by a double trunnion 58, adaptable to a recess 59 provided within the bottom part of striking face 4 of coupler head 2 of FIGURE 10.

The transition gear represented by FIGURE 11 appears of more intricate design than the normal shackle arrangement, which comprises two nuts and only one screw portion having inversely threaded ends.

This shackle can give liberty for hitching and for shortening of headstock distances required in traffic, because both its ends are attached pretty near the headstocks of vehicles to be attached. When however an automatic coupler is present on one of the vehicles to be coupled, dormant part of shackle cannot be fixed as far back as the permanent articulation at the rear of hook, because this would entail removing about the bottom half of coupler casting. The position according to the invention and shown in FIGURES 9 and has been developed as the best possible for reducing lateral sway in curves sufficiently to avoid interference with knuckle or coupler parts, for allowing gear to be safely moored out of harms way in order to free the room required for automatic performance, without endangering the strength of the automatic coupler as such.

It should be understood i but a vehicle intended to meet a car fitted with the hook arrangement should have side buffers, since hook-equipped stock is designed to receive bulfing stresses on the two side buffers, and not in centre of headstock. Contacting buffers should keep vehicles far enough apart to avoid any fouling between coupler knuckle and opposite hook, whilst the transition gear should permit to obtain suificient length for the end shackle to be hitched manually over the opposite hook; afterwards the screw gear is to be shortened in order to give the required precornpression of buffers. For this reason, recourse was had to the hollow screw with the object of allowing to reach minimum distance between headstocks.

Moreover, within the narrow compass of coupler head 2, a strong and compact fixation had to be developed for the transition gear, without reducing the strength as such of the automatic coupler, which having to survive after conversion, has to expect heavier loads from the evolution of traffic. This was done by means of the double trunnion traction arrangements 56 and 58. Those arrangements (1) give broad flexibility in the vertical plane, required for general use mobility and also in conjunction with articulation of nut 52 to allow gear to be safely hitched to hook 6-5 for liberating inside of contour required for automatic operation. (2) give a slight transverse mobility, their bearing faces in traction being feebly toroidal in conjunction with the small play permitted laterally by the slots of their containing pockets and transition radii. (3) have their areas notably relieved towards the trunnion ends, so as to give a maximum aptitude to flexibly resist dynamic stresses.

Containing pockets are in principle designed on similar lines with surface conditions to match, stress having been laid on maintaining continuous lateral walls.

Whereas the lateral walls of gear carrier 57 are adapted for transmission of such tractive efforts as may be borne by the transition screw gear, walls 60 and 61 of fixed pockets 59 have supplementarily to hold up the strength of striking face 4 of coupler head, which would appear to be weakened by the transverse cut made through it for the passage of screw arrangement. Longitudinal walls 60, 61 take a firm seating on back face 62, also of extra thickness, and walls 60, 61 are moreover braced by ledges 63, 64 which curve hook-like around double trunnion, the whole forming a box-like columnar block strongly strutted rearwardly as a substitute for the normal structure of bottom striking face 4 in an ordinary coupler. Gear-carrier has also been cut away at 66 in order to afford possibility of continuing as far as possible bottom wall of coupler box casting 2 by which wing 10 is joined to the shank.

Articulation of double trunnion 58 is brought in the vertical sense as near as possible to horizontal central plane of automatic coupler, which entails some dissymtmetry of knuckle lock face, appositely discharging wing 10 whilst wing 9 which is more loaded can be strengthened adequately.

Double trunnion 58 is hooked into its lodgement 59 in coupler head before knuckle 5 is adapted in its position; and conditions are such that as long as the knuckle is fitted double trunnion 58 is unable to escape, its passage being always covered by some portion of knuckle tail sector.

Gear carrier 57 is provided with salient lugs 66 which in the course of transitional traction register with corresponding surfaces on bottom knuckle hub in order to avoid untoward rubbing of threaded parts 55, and to prevent unwelcome closure of knuckle, thus supporting the action of spring 70 coiled around pivot 7 in order to keep knuckle normally open.

It will thus be seen that thanks to these measures an automatic coupler may be constructed of seriously increased strength, and furthermore adapted to the pecularities of exacting service. Especially for the case of transi tion an automatic coupler may be adapted to take a screw coupling of normal strength for intermediary period, whilst the automatic portion which is to survive is fully adequate to future increased trafiic.

The invention is not to be undrestood as restricted to the details illustrated and described but may be modified within the scope of appended claims without departing from the spirit and scope of the invention.

I claim:

1. An automatic coupling mechanism comprising a coupler casting for connection with a car structure through a compressible draft gear or the like, a pivot pin positioned within said coupler casting, a knuckle rotatable around said pivot pin, first corresponding ribs formed on the rear of said coupler casting and the rear of said knuckle respectively and adapted, when engaged, to afford functioning of said knuckle as a curved link for transmitting to said rear of said coupler casting the major portion of the pulling forces applied to the mechanism, second corresponding ribs formed on said coupler casting and said knuckle respectively and disposed rearwardly of said pivot pin and forwardly of said first ribs, said second corresponding ribs being spaced apart so as to be adapted to engage and thus transmit pulling forces to said casting in response to engagement and yielding of said first ribs, and third corresponding ribs formed on said coupler casting and said knuckle respectively and disposed forwardly of said pivot pin, said third ribs being spaced apart further than said second ribs so as to be adapted to engage and thus transmit pulling forces to said casting in response to yielding of said first and second corresponding ribs.

2. An automatic coupling mechanism comprisng a coupler casting for connection with a car structure through a compressible draft gear or the like, said coupler casting having knuckle-carrying wing means at one of its sides and a guard arm at its other side, a knuckle having a hub portion, a pivot pin for rotatably mounting said knuckle at its hub portion carried by said wing means, said pivot pin being offset laterally outwardly with respect to the center of said knuckle hub so as to provide a larger crosssectional area at the inside portion of said hub which is subjected to tension when tractive forces are applied to said knuckle and to increase the coupling capacity of said coupler.

3. An automatic coupling mechanism comprising a coupler casting for connection with a car structure through a compressible draft gear or the like, said coupler casting having knuckle-carrying wing means at one of its sides and a guard arm at its other side, a pivot pin carried by said wing means for positioning the same within said coupler casting, a knuckle rotatable around said pivot pin, said knuckle as its rear having integral upper and lower lugs substantially concentric with the axis of said pivot pin, said coupler casting at its rear having integral arcuate ledges conforming to and engageable with said lugs of said knuckle, and said coupler casting having an integral vertical lug at its said one side adapted to be engaged by the tail end at one side of said knuckle.

4. An automatic coupling mechanism comprising a coupler casting for connection with a car structure through a compressible draft gear or the like, said coupler casting having knuckle-carrying wing means atone of its sides and a guard arm at its other side, a pivot pin carried by said wings for positioning the same within said coupler casting, a knuckle rotatable around said pivot pin, said knuckle at its rear having integral upper and lower lugs substantially concentric with the axis of said pivot pin, said coupler casting at its rear having integral arcuate ledges conforming to and engageable with said lugs of said knuckle, said coupler casting having an integral vertical lug at its said one side adapted to be engaged by the tail end at one side of said knuckle, said knuckle having a vertical locking face at the other side of its tail end, a lock adapted to be disposed between said locking face and an inside surface of said other side of said coupler casting and said locking face and said lock having interengaging vertically extending lug and ledge elements, respectively.

5. An automatic coupling mechanism comprising a coupler casting for connection with a car structure through a compressible draft gear or the like, said coupler casting having knuckle-carrying wing means at one of its sides and a guard arm at its other side, a pivot pin carried by said wing means for positioning the same within said coupler casting, a knuckle rotatable around said pivot pin, said knuckle at its rear having integral upper and lower lugs substantially concentric with the axis of said pivot pin, said coupler casting at its rear having integral arcuate ledges conforming to and engageable with said lugs of said knuckle, said coupler casting having an integral vertical lug at its said one side adapted to be engaged by the tail end at one side of said knuckle, said knuckle having a vertical locking face at the other side of its tail end, a lock adapted to be disposed between said vertical locking face of said knuckle and an inside vertical surface of said other side of said coupler casting for locking said knuckle against rotation, said lock having an upwardly protruding ledge at its rear top edge, said coupler casting having a backwall provided with a depending ridge, and means for mounting said lock to dispose said ledge under said ridge in abutting relation as said lock approaches its locking position.

6. An automatic coupling mechanism comprising a coupler casting for connection with a car structure through a compressible draft gear or the like, said coupler casting having knuckle-carrying wing means at one of its sides and a guard arm at its other side, a pivot pin carried by said wing means for positioning the same within said coupler casting, a knuckle rotatable around said pivot pin, said knuckle at its rear having integral upper and lower lugs substantially concentric with the axis of said pivot pin, said coupler casting at its rear having integral arcuate ledges conforming to and engageable with said lugs of said knuckle, said coupler casting having an integral vertical lug at its said one side adapted to be engaged by the tail end at one side of said knuckle, said knuckle having a vertical locking face at the other side of its tail end, a lock of a substantially solid mass adapted to be disposed between said vertical locking face of said knuckle and an inside vertical surface of said other side of said coupler casting, lock actuating means of substantially less mass than said lock, and means connecting said lock actuating means with said lock for positioning the latter in its locking and unlocking positions.

7. For use in conjunction with railway car automatic mechanism, transition gear mechanism comprising a shackle adapted to be hitched over a component of an adjacent car, a threaded nut journalled in said shackle, a hollow tube threaded in said nut, a handle for rotating said threaded tube in said nut, said tube being internally threaded in reverse direction to the threading of said nut, a screw threaded into said tube, said screw having a double trunnion at its outer end, a transition gear carrier for receiving the said double trunnion of said screw, and said transition gear carrier having a double trunnion for attachment of the transition gear means in a recess of an automatic coupler casting.

8. For use in conjunction with railway car automatic coupling mechanism, transition gear mechanism comprising a shackle adapted to be hitched over a component of an adjacent car, an internally threaded nut connected to said shackle, a hollow tube threaded in said nut, a handle for rotating said threaded tube in said nut, said tube being internally threaded in reverse direction to the threading of said nut, a screw threaded into said tube, and means for connecting said screw to an automatic coupler casting,

9. An automatic coupling mechanism comprising a coupler casting for connection with a car structure through a compressible draft gear or the like, said coupler casting having knuckle-carrying wing means at one of its sides and a guard arm at its other side, a pivot pin carried by said wing means for positioning the same within said coupler casting, a knuckle rotatable around said pivot pin, said knuckle having a vertical locking face at one side of its tail end, a lock adapted to be disposed between said vertical locking face and an inside vertical surface of an adjacent side of said coupler casting for locking said knuckle against rotation, said lock having an upwardly protruding ledge at its rear top edge, said coupler casting having a ba-ckwall provided with a first depending ridge, means for mounting said lock to dispose said ledge under said first ridge to prevent accidental unlocking thereof, a second depending ridge on said backwall of said coupler casting, and lock lifting means operatively associated with said lock and disposed under said second ridge when in its lowered position so as to further provide against accidental unlocking of said lock.

References Cited in the file of this patent UNITED STATES PATENTS 709,338 Lennon Sept. 16, 1902 1,104,516 Krakau July 21, 1914 1,203,319 Durbin Oct. 31, 1916 1,614,518 Willison Jan. 18, 1927 1,615,946 Kinne Feb. 1, 1927 1,696,040 Kelso Dec. 18, 1928 1,876,816 Wittmer Sept. 13, 1932 1,989,027 Smith Jan. 22, 1935 2,548,479 Kayler Apr. 10, 1951 FOREIGN PATENTS 667,581 Great Britain 5, 1952 

9. AN AUTOMATIC COUPLING MECHANISM COMPRISING A COUPLER CASTING FOR CONNECTION WITH A CAR STRUCTURE THROUGH A COMPRESSIBLE DRAFT GEAR OR THE LIKE, SAID COUPLER CASTING HAVING KNUCKLE-CARRYING WING MEANS AT ONE OF ITS SIDES AND A GUARD ARM AT ITS OTHER SIDE, A PIVOT PIN CARRIED BY SAID WING MEANS FOR POSITIONING THE SAME WITHIN SAID COUPLER CASTING, A KNUCKLE ROTATABLE AROUND SAID PIVOT PIN, SAID KNUCKLE HAVING A VERTICAL LOCKING FACE AT ONE SIDE OF ITS TAIL END, A LOCK ADAPTED TO BE DISPOSED BETWEEN SAID VERTICAL LOCKING FACE AND AN INSIDE VERTICAL SURFACE OF AN ADJACENT SIDE OF SAID COUPLER CASTING FOR LOCKING SAID KNUCKLE AGAINST ROTATION, SAID LOCK HAVING AN UPWARDLY PROTRUDING LEDGE AT ITS REAR TOP EDGE, SAID COUPLER CASTING HAVING A BACKWALL PROVIDED WITH A FIRST DEPENDING RIDGE, MEANS FOR MOUNTING SAID LOCK TO DISPOSE SAID LEDGE UNDER SAID FIRST RIDGE TO PREVENT ACCIDENTAL UNLOCKING THEREOF, A 